It seems like a fun ride if your and electron you see NADH and FADH act as electron stores or transporters and when they get to complex I of the electron transport chain the electrons are passed from the molecules to complex and then from that complex to the other complexes. NADH is oxidized to NAD in this process and at Complex II FADH is oxidised adding more electrons for the chain.
So basically the electrons are fully of energy like “YEAHH this is fun” as they move from complex to complex
However as the electrons move through the chain from complex to complex they lose their energy thus at complex III, no additional electrons enter the chain, but electrons from complexes I and II flow through it.
When electrons arrive at complex IV, they are transferred to a molecule of oxygen. When the oxygen, get the electrons water is produced and so the electrons are like “aww i just so tired i had enough i think ill just turn into water and chill.”
But its not just a free fun ride it serious business because while these electron ride from complex to complex, H+ move through complexes I-IV from the matix to the outside the membrane or in the intermembrane space where it accumulates. As a result, a net negative charge builds up in the matrix space while a net positive charge builds up in the intermembrane space this is where the last complex comes into play this complex is called ATP synthase.
In an attempt to meet and equilibrium between the charges the H+ in the intermembrane space tries to find a way back into the matrix however the only way back is through the ATP synthase molecule that harnesses the energy of the H+ flowing back into the matrix and thus in the process uses the energy to make ATP by combing ADP +Pi. This process is also called oxidative .phosphorelation and this process takes place within the intermembrane of the mitochondria.
here is another really cool way of looking at it
Well i am almost at the end of this blog but i did promise you one last video and that video would be on protein denaturing and then we end with a bang 😀 i hope you had fun with me on my biochem journey ….